Numerical modeling of venting of particle-driven gravity currents in reservoirs

Resumo

Sedimentation in reservoirs results in loss of their storage capacity and impacts the fauna where it is
located. Therefore, effective sediment management is an important task to increase reservoir lifetime and mitigate
the damage that sedimentation may cause. Turbidity currents are the primary source of sediments in reservoirs.
Venting them reduces sedimentation. Numerical models are an efficient tool for studying venting. In this work, we
have introduced a model to predict the flow of particle-driven gravity currents, and we apply it to study the venting
process in reservoirs. The mathematical models result from the incompressible Navier-Stokes equations combined
with an advection-diffusion transport equation for suspended sediments. We implement the mathematical model
in libMesh, an open finite element library that provides a framework for multiphysics numerical simulations.
The model is successfully verified and validated using literature data of lock exchange experiments. We test the
capability of the model to optimize the venting of turbidity currents as an efficient sediment management strategy
for reservoirs. The results show that the concentration field during venting agrees well with observations from
laboratory experiments.